Hi, I am using libvirt with qemu/kvm with qemu-guest-agent and suspend/save/resume linux and windows vm's. Time in Windows gets handled fine with ntp but I can get neither ntp or chrony to sync after resume without manually setting the time close to correct first. Searching has gotten me to the point where I can manually set the time using qemu-guest-agent but I cant figure out how to get libvirt to automaticly trigger this on resume. I am finding information saying it works but not how, or that its still work in progress and not implemented yet (but patches exist). Can someone either say "its not working yet" or explain what I am missing please?

On 29/09/14 16:28, Martin Kletzander wrote: > On Fri, Sep 26, 2014 at 08:16:25AM +0800, Bill Kenworthy wrote: >> Hi, >> I am using libvirt with qemu/kvm with qemu-guest-agent and >> suspend/save/resume linux and windows vm's. Time in Windows gets >> handled fine with ntp but I can get neither ntp or chrony to sync after >> resume without manually setting the time close to correct first. >> >> Searching has gotten me to the point where I can manually set the time >> using qemu-guest-agent but I cant figure out how to get libvirt to >> automaticly trigger this on resume. I am finding information saying it >> works but not how, or that its still work in progress and not >> implemented yet (but patches exist). Can someone either say "its not >> working yet" or explain what I am missing please? >> > > What version of libvirt are you using? Since 1.2.5 there's > virDomainSetTime() API that can do this and since 1.2.8 it's called > automatically after resume. > > Martin Thanks Martin for replying. I am using 1.2.6. I presume that there is no way to get 1.2.6 to trigger it after resume (has to be manual) so I'll have to upgrade to 1.2.8.

On 09/29/2014 02:28 AM, Martin Kletzander wrote: > On Fri, Sep 26, 2014 at 08:16:25AM +0800, Bill Kenworthy wrote: >> Hi, >> I am using libvirt with qemu/kvm with qemu-guest-agent and >> suspend/save/resume linux and windows vm's. Time in Windows gets >> handled fine with ntp but I can get neither ntp or chrony to sync after >> resume without manually setting the time close to correct first. >> >> Searching has gotten me to the point where I can manually set the time >> using qemu-guest-agent but I cant figure out how to get libvirt to >> automaticly trigger this on resume. I am finding information saying it >> works but not how, or that its still work in progress and not >> implemented yet (but patches exist). Can someone either say "its not >> working yet" or explain what I am missing please? >> > > What version of libvirt are you using? Since 1.2.5 there's > virDomainSetTime() API that can do this and since 1.2.8 it's called > automatically after resume. Umm, I have a problem with that statement. Anything that requires guest interaction (which guest-agent set-time does) must NOT default to being automatic; it is only safe to enable if explicitly allowed. What is the domain XML that must be explicitly set in order to turn on automatic time-set after resume?

On 10/02/2014 04:01 AM, Martin Kletzander wrote: >>> What version of libvirt are you using? Since 1.2.5 there's >>> virDomainSetTime() API that can do this and since 1.2.8 it's called >>> automatically after resume. >> >> Umm, I have a problem with that statement. Anything that requires guest >> interaction (which guest-agent set-time does) must NOT default to being >> automatic; it is only safe to enable if explicitly allowed. What is the >> domain XML that must be explicitly set in order to turn on automatic >> time-set after resume? >> > > Oh, sorry, my fault. I was under the impression that Michal created > the API especially for this purpose, but looking at the code it's not > done automatically. At one point, I seem to recall a proposal of adding an <on_resume> tag to domain xml that could explicitly request time resync each time the domain is resumed; but I don't know if anyone implemented it yet.